From a very young age, astronomy has been a subject of interest to me. However, I was also curious about what makes up everything. This is a naive attempt from my end to explain electromagnetism and quantum mechanics, the world of small things. I am unsure how many parts it may split into, as I am just going with the flow here.

Part one

How do we communicate?

It all began during my bike commute to the workspace. I often use this time to listen to podcasts (I couldn't listen to music these days, maybe just a phase!?). One one of the days, I tried to use ChatGPT's voice mode to talk to, but it had severe latency. My immediate thought blamed the 5G network, however a part of my quirky brain briefly wondered if there is a very teeny-tiny possibility that Bluetooth could buffer the data and stream it back with a delay, like how queues work. I knew the question was stupid and highly unlikely but I still went ahead and tried to justify to my other half of the brain on why that cant be the case.

In order to justify, I had to learn how exactly Bluetooth(BLE) works and if there is working memory as such that partly buffers the stream. Apparently there is one, but the buffer is too negligible to notice for any such real world scenario and plays no role in delays. So, its mostly fire and forget. I learned that BLE transmits via radio waves (overlaps with 2.4 GHz microwave frequency - same as our WiFi), so the bottleneck must obviously be my internet connection after all.

I was explaining how the internet works to my other friends. I can break it down further into a separate post maybe sometime.

In short, every communication happens by tweaking the same EM Spectrum, using radio waves or microwaves for most part. We communicate through light.

This led me to a series of fundamental questions that I tried answering myself.

  • How do signals travel through a vacuum without a physical medium?
    • We use the electromagnetic field.
  • If sound needs air to vibrate, how do radio waves carry information across the void?
    • We carry low energy photons through the electromagnetic field.
  • How do we produce light as radio waves, and what is light anyway?
    • Packets of low energy photons through the electromagnetic field
  • Finally, why do we use radio waves instead of the visible light that we can see?
    • Well they are low energy photons so it wont burn your device easily

More importantly, however apparent the answers turn out to be, most of them had this wording "low energy photons", and there was a thought that kept itching my brain. How can we just 'emit photons' out of nothing? It feels so strange when we know that energy cannot be created or destroyed. The law of conservation as we call it. Imagining photons as particles confused me big time. If they are particles, how come all individual packets of particles carry same energy. The particle nature fails big time in this context. So it must obviously be waves.

Wait, so if we are emitting energy, I asked myself another absurd question. Do we decay any material? ABSOLUTELY NOT! So whats happening? How do we produce energy? Whats EM Field? So many questions..

Instead of answering from what I knew, I went ahead to brush up my fundamentals. I listened to good old Feynman lectures and other YT videos in general.

Here is what happens: we use electrical energy (like from a battery) to oscillate electrons up and down of a teeny tiny antenna that is used as an emitter in the BLE. This isn't magic, we have perfected the tech in such a way that the electrons that accelerate and shake converts the electrical energy into ripples in the universal electromagnetic field. Nothing else! They spread out just like the ripples you see moving through a pool of water after throwing a stone. These ripples travel through empty space as electromagnetic waves. So, when these waves hit a receiver, they shake the receiver's electrons in the exact same pattern. But the information is never lost because its a wave! We have fine-tuned this technology so beautifully that these intercepted vibrations can be decoded into digital 0s and 1s, and ultimately, into the information we see on our screens.

Now the bigger question, what did I mean by Universal Electromagnetic Field. What that ripple is made of? For a moment, I paused. In the 19th century, physicists like Maxwell predicted that there had to be a medium called 'Ether' for light to propagate. But we couldn't prove it, and in 1887, it was definitively disproven. So there is no ether, but there is still something. The field exists. It is almost as fundamental as the space-time fabric itself. We are in it, surrounded by it. We feel its physical presence whenever we bring two magnets together, when we look at light that has traveled across the cosmos without losing energy, or when we communicate by oscillating electrons! :)

Which leads to an even bigger question: what exactly is energy inside this invisible field, and how is it truly conserved? What are those ripples?

More to it in Part two.